JP2004324506A - Controlling device for internal combustion engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To approximately make an engine brake effect at a partial cylinder operation equal to the engine brake effect at a full cylinder operation by appropriately controlling an engine intake air amount at deceleration. <P>SOLUTION: During deceleration of an engine 1, when the full cylinder operation is performed, a dash pot control item THDP is added to an idle target opening THIDL, thereby calculating a target opening THCMD of a throttle valve (S38). When the partial cylinder operation is performed, the target opening THCMD is set to a value of multiplying the idle target opening THIDL by deceleration correction factor KDEC1 or KDEC2 which is less than 1 (S40, S41). A throttle valve opening TH is controlled so as to be match with the target opening THCMD. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a control device for an internal combustion engine, and more particularly to a control device for an internal combustion engine having a cylinder deactivation mechanism that deactivates a part of a cylinder of an internal combustion engine having a plurality of cylinders.
[0002]
[Prior art]
Patent Literature 1 discloses an internal combustion engine provided with a cylinder deactivation mechanism. A partial cylinder operation for deactivating a part of a plurality of cylinders and an all-cylinder operation for operating all the cylinders are performed in an engine operating state. Is switched in accordance with.
[0003]
[Patent Document 1]
JP-A-8-105339
[Problems to be solved by the invention]
FIG. 12 is a diagram showing the relationship between the throttle valve opening TH of the internal combustion engine and the absolute pressure PBA in the intake pipe (when the engine speed is kept constant), and the solid line in FIG. , The broken line corresponds to partial cylinder operation. As is clear from this figure, when the throttle valve opening TH is the same, the absolute pressure PBA in the intake pipe is higher during partial cylinder operation than during all cylinder operation. Therefore, during partial cylinder operation, the engine braking effect (the degree of effectiveness of engine braking) is smaller than during full cylinder operation.
[0005]
The present invention has been made by paying attention to this point, and it is necessary to appropriately control the engine intake air amount at the time of deceleration and to make the engine braking effect at the time of partial cylinder operation substantially equal to that at the time of all cylinder operation. It is an object of the present invention to provide a control device for an internal combustion engine that can be used.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 has a plurality of cylinders, an all-cylinder operation for operating all of the plurality of cylinders, and a partial cylinder for suspending the operation of some of the plurality of cylinders. In a control device for an internal combustion engine provided with a switching means (30) for switching between operation and operation, an operation parameter (TW, TA, TH, NE, VP, GP, GP, etc.) of a vehicle driven by the engine, including an operation parameter of the engine. Operating parameter detecting means for detecting the AP), command means for instructing the switching means (30) to perform the all-cylinder operation or the partial cylinder operation in accordance with the operating parameter detected by the operating parameter detecting means, and the engine A control valve (3) for controlling an intake air amount of the engine, an intake air amount control means for controlling an opening degree of the control valve (3), and an operating parameter. Deceleration determining means for determining the deceleration of the engine according to the operating parameter detected by the detecting means, wherein the intake air amount control means determines that the engine is being decelerated by the deceleration determining means Wherein the opening of the control valve (3) is smaller when the partial cylinder operation is being performed than when the full cylinder operation is being performed.
[0007]
According to this configuration, the opening degree of the intake air amount control valve is controlled to be smaller when partial cylinder operation is being performed during deceleration of the engine than when all cylinder operation is being performed. . Therefore, the intake pipe pressure during the partial cylinder operation and the intake pipe pressure during the full cylinder operation become substantially the same, and substantially the same engine braking effect can be obtained.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a configuration of an internal combustion engine and a control device thereof according to an embodiment of the present invention. A V-type six-cylinder internal combustion engine (hereinafter simply referred to as “engine”) 1 includes a right bank provided with # 1, # 2 and # 3 cylinders, and a left bank provided with # 4, # 5 and # 6 cylinders. The right bank is provided with a cylinder deactivation mechanism 30 for temporarily deactivating the # 1 to # 3 cylinders. FIG. 2 is a diagram showing a hydraulic circuit for hydraulically driving the cylinder deactivation mechanism 30 and a control system thereof. This diagram is also referred to in conjunction with FIG.
[0009]
A throttle valve 3 is arranged in the intake pipe 2 of the engine 1. The throttle valve 3 is provided with a throttle valve opening sensor 4 for detecting the opening TH of the throttle valve 3, and a detection signal is supplied to an electronic control unit (hereinafter, referred to as “ECU”) 5. An actuator 24 that drives the throttle valve 3 is connected to the throttle valve 3, and the operation of the actuator 24 is controlled by the ECU 5.
[0010]
The fuel injection valve 6 is provided for each cylinder slightly upstream of an intake valve (not shown), and each injection valve is connected to a fuel pump (not shown) and electrically connected to the ECU 5 to output a signal from the ECU 5. Thus, the valve opening time of the fuel injection valve 6 is controlled.
[0011]
Immediately downstream of the throttle valve 3, an intake pipe absolute pressure (PBA) sensor 7 is provided. The absolute pressure signal converted into an electric signal by the absolute pressure sensor 7 is supplied to the ECU 5. An intake air temperature (TA) sensor 8 is attached downstream of the intake pipe absolute pressure sensor 7, detects the intake air temperature TA, and supplies a corresponding electric signal to the ECU 5.
[0012]
The engine water temperature (TW) sensor 9 mounted on the main body of the engine 1 is composed of a thermistor or the like, detects the engine water temperature (cooling water temperature) TW, outputs a corresponding temperature signal, and supplies it to the ECU 5.
The ECU 5 is connected to a crank angle position sensor 10 for detecting a rotation angle of a crankshaft (not shown) of the engine 1, and supplies a signal corresponding to the rotation angle of the crankshaft to the ECU 5. The crank angle position sensor 10 outputs a pulse (hereinafter, referred to as “CYL pulse”) at a predetermined crank angle position of a specific cylinder of the engine 1, and relates to a top dead center (TDC) at the start of an intake stroke of each cylinder. A TDC sensor that outputs a TDC pulse at a crank angle position before a predetermined crank angle (every 120 degrees of crank angle in a 6-cylinder engine) and a CRK that generates a CRK pulse at a constant crank angle cycle shorter than the TDC pulse (for example, a 30-degree cycle). A CYL pulse, a TDC pulse, and a CRK pulse are supplied to the ECU 5. These signal pulses are used for various timing controls such as fuel injection timing, ignition timing, and the like, and detection of the engine speed (engine speed) NE.
[0013]
The cylinder deactivation mechanism 30 is hydraulically driven using lubricating oil of the engine 1 as hydraulic oil. The hydraulic oil pressurized by the oil pump 31 is supplied to the cylinder deactivation mechanism 30 via the oil passage 32, the intake oil passage 33i, and the exhaust oil passage 33e. An intake-side solenoid valve 35i and an exhaust-side solenoid valve 35e are provided between the oil passage 32 and the oil passages 33i and 33e, and these solenoid valves 35i and 35e are connected to the ECU 5 and the operation thereof is performed by the ECU 5. Controlled.
[0014]
The oil passages 33i, 33e are provided with oil pressure switches 34i, 34e that are turned on when the operating oil pressure falls below a predetermined threshold value, and a detection signal thereof is supplied to the ECU 5. A hydraulic oil temperature sensor 33 for detecting a hydraulic oil temperature TOIL is provided in the middle of the oil passage 32, and a detection signal is supplied to the ECU 5.
[0015]
A specific configuration example of the cylinder deactivation mechanism 30 is disclosed in, for example, Japanese Patent Application Laid-Open No. 10-103097, and a similar mechanism is used in the present embodiment. According to this mechanism, when the solenoid valves 35i and 35e are closed and the operating oil pressure in the oil passages 33i and 33e is low, the intake valves and the exhaust valves of the cylinders (# 1 to # 3) normally open and close. On the other hand, when the solenoid valves 35i and 35e are opened and the operating oil pressure in the oil passages 33i and 33e increases, the intake valves and the exhaust valves of the cylinders (# 1 to # 3) maintain the closed state. That is, while the solenoid valves 35i and 35e are closed, all-cylinder operation for operating all the cylinders is performed. When the solenoid valves 35i and 35e are opened, the cylinders # 1 to # 3 are deactivated, and the cylinders # 4 to # 4 are stopped. A partial cylinder operation in which only the # 6 cylinder is operated is performed.
[0016]
An exhaust gas recirculation passage 21 is provided between the exhaust pipe 13 and the downstream side of the throttle valve 3 of the intake pipe 2. An “EGR valve” 22) is provided. The EGR valve 22 is an electromagnetic valve having a solenoid, and its valve opening is controlled by the ECU 5. The EGR valve 22 is provided with a lift sensor 23 for detecting the valve opening (valve lift amount) LACT, and a detection signal is supplied to the ECU 5. The exhaust gas recirculation passage 21 and the EGR valve 22 constitute an exhaust gas recirculation mechanism.
[0017]
The ignition plug 12 provided for each cylinder of the engine 1 is connected to the ECU 5, and a drive signal of the ignition plug 12, that is, an ignition signal is supplied from the ECU 5.
The ECU 5 includes an atmospheric pressure sensor 14 for detecting an atmospheric pressure PA, a vehicle speed sensor 15 for detecting a traveling speed (vehicle speed) VP of a vehicle driven by the engine 1, and a gear position sensor for detecting a gear position GP of a transmission of the vehicle. 16 and an accelerator sensor 17 for detecting an accelerator pedal depression amount (hereinafter referred to as “accelerator pedal operation amount”) AP of the vehicle, and detection signals of these sensors are supplied to the ECU 5.
[0018]
The ECU 5 has an input circuit having a function of shaping input signal waveforms from various sensors, correcting a voltage level to a predetermined level, and converting an analog signal value to a digital signal value, a central processing circuit (hereinafter, “CPU”). ), A storage circuit for storing various calculation programs executed by the CPU, calculation results and the like, an output circuit for supplying a drive signal to the fuel injection valve 6, and the like. The ECU 5 controls the opening time of the fuel injection valve 6, the ignition timing, and the opening degree of the EGR valve 22 based on the detection signals of the various sensors, and also opens and closes the solenoid valves 35i and 35e, thereby controlling the entire operation of the engine 1. Switching control between the cylinder operation and the partial cylinder operation is performed. Further, the ECU 5 calculates the target opening THCMD of the throttle valve 3 according to the accelerator pedal operation amount AP, and controls the drive of the actuator 24 so that the detected throttle valve opening TH matches the target opening THCMD.
[0019]
FIG. 3 is a flowchart of a process for determining an execution condition of cylinder deactivation (partial cylinder operation) for deactivating some cylinders. This process is executed by the CPU of the ECU 5 every predetermined time (for example, every 10 milliseconds).
In step S11, it is determined whether or not the start mode flag FSTMOD is "1". If FSTMOD = 1 and the engine 1 is being started (cranking), the detected engine coolant temperature TW is used as the start mode coolant temperature. It is stored as TWSTMOD (step S13). Next, the TMTWCSDLY table shown in FIG. 4 is searched according to the start mode water temperature TWSTMOD, and the delay time TMTWCSDLY is calculated. In the TMTWCSDLY table, the delay time TMTWCSDLY is set to the predetermined delay time TDLY1 (for example, 250 seconds) when the start mode water temperature TWSTMOD is equal to or lower than the first predetermined water temperature TW1 (for example, 40 ° C.), and the start mode water temperature TWSTMOD is set to the first predetermined water temperature. In a range higher than TW1 (eg, 40 ° C.) and equal to or lower than the second predetermined water temperature TW2 (eg, 60 ° C.), the delay time TMTWCSDLY is set to decrease as the start mode water temperature TWSTMOD increases, and the start mode water temperature TWSTMOD is set to the second predetermined water temperature. In a range higher than TW2, the delay time TMTWCSDLY is set to “0”.
[0020]
In the following step S15, the down count timer TCSWAIT is set to the delay time TMTWCSDLY and started, and the cylinder deactivation flag FCYLSTP is set to "0" (step S24). This indicates that the execution condition of the cylinder deactivation is not satisfied.
[0021]
When FSTMOD = 0 and the normal operation mode is set in step S11, it is determined whether or not the engine coolant temperature TW is higher than a cylinder deactivation determination temperature TWCSTP (for example, 75 ° C.) (step S12). When TW ≦ TWCSTP, it is determined that the execution condition is not satisfied, and the process proceeds to step S14. If the engine coolant temperature TW is higher than the cylinder deactivation determination temperature TWCSTP, the process proceeds from step S12 to step S16, and it is determined whether or not the value of the timer TCSWAIT started in step S15 is "0". While TCSWAIT> 0, the process proceeds to step S24, and when TCSWAI = 0, the process proceeds to step S17.
[0022]
In step S17, the THCS table shown in FIG. 5 is searched according to the vehicle speed VP and the gear position GP, and the upper threshold value THSHSH and the lower threshold value THCSL used for the determination in step S18 are calculated. In FIG. 5, a solid line corresponds to the upper threshold value THCSH, and a broken line corresponds to the lower threshold value THCSL. The THCS table is set for each gear position GP. At each gear position (second to fifth speeds), the upper threshold value THSHSH and the lower threshold value THCSL increase as the vehicle speed VP increases. Have been. However, when the gear position GP is the second speed, an area is provided in which the upper threshold value THSHSH and the lower threshold value THCSL are kept constant even when the vehicle speed VP changes. When the gear position GP is in the first speed, the all-cylinder operation is always performed, so the upper threshold value THSHSH and the lower threshold value THCSL are set to, for example, “0”. If the vehicle speeds VP are the same, the thresholds (THSHSH, THCSL) corresponding to the low-speed gear position GP are set to values larger than the thresholds (THCSH, THCSL) corresponding to the high-speed gear position GP.
[0023]
In step S18, it is determined with a hysteresis whether the throttle valve opening TH is smaller than a threshold value THCS. Specifically, when the cylinder deactivation flag FCYLSTP is “1”, when the throttle valve opening TH increases and reaches the upper threshold value THSHSH, the answer to step S18 is negative (NO), and the cylinder deactivation flag FCYLSTP is set. When it is "0", the answer to step S18 becomes affirmative (YES) when the throttle valve opening TH decreases and falls below the lower threshold value THCSL.
[0024]
When the answer to step S18 is affirmative (YES), it is determined whether or not the atmospheric pressure PA is equal to or higher than a predetermined pressure PACS (for example, 86.6 kPa (650 mmHg)) (step S19), and the answer is affirmative (YES). ), It is determined whether the intake air temperature TA is equal to or higher than a predetermined lower limit temperature TACSL (for example, −10 ° C.) (step S20), and if the answer is affirmative (YES), the intake air temperature TA It is determined whether or not the temperature is lower than an upper limit temperature TACSH (for example, 45 ° C.) (step S21). If the answer is affirmative (YES), it is determined whether or not the engine speed NE is lower than a predetermined speed NECS. (Step S22). The determination in step S22 is performed with hysteresis as in step S18. That is, when the cylinder deactivation flag FCYLSTP is “1”, when the engine speed NE increases and reaches the upper rotation speed NECSH (for example, 3500 rpm), the answer to step S22 becomes negative (NO), and the cylinder deactivation flag FCYLSTP Is "0", when the engine speed NE decreases and falls below the lower engine speed NECSL (for example, 3300 rpm), the answer to step S22 becomes affirmative (YES).
[0025]
When the answer to any of steps S18 to S22 is negative (NO), it is determined that the execution condition of the cylinder deactivation is not satisfied, and the process proceeds to step S24. On the other hand, when all the answers of steps S18 to S22 are affirmative (YES), it is determined that the execution condition of the cylinder deactivation is satisfied, and the cylinder deactivation flag FCYLSTP is set to "1" (step S23).
[0026]
When the cylinder deactivation flag FCYLSTP is set to “1”, the cylinders # 1 to # 3 are deactivated and the cylinder deactivation flag FCYLSTP is set to “0” by executing the partial cylinder operation of operating the cylinders # 4 to # 6. Is set, the all-cylinder operation for operating all the cylinders # 1 to # 6 is executed.
[0027]
FIG. 6 is a flowchart of a process for calculating the target opening THCMD of the throttle valve. This process is executed by the CPU of the ECU 5 every predetermined time (for example, every 10 milliseconds).
In step S31, a basic target opening THAP is calculated according to the accelerator pedal operation amount AP and the engine speed NE. The basic target opening THAP is set so as to be substantially proportional to the throttle valve opening TH. In step S32, the target idle opening THIDL is calculated according to the engine coolant temperature TW, the operating state of the generator driven by the engine 1, the operating state of the air conditioner driven by the engine 1, and the like. The idle target opening THIDL is a target opening when the accelerator pedal operation amount AP is “0” (a state in which the accelerator pedal is not depressed).
[0028]
In step S33, it is determined whether or not the deceleration flag FDEC is "1". When the accelerator pedal operation amount AP is “0” and the vehicle speed VP is equal to or higher than a predetermined vehicle speed VPDEC (for example, 10 km / h), it is determined that the engine 1 is decelerating, and the deceleration flag FDEC is set to “1” by a process not shown. Is set to When FDEC = 0 in step S33 and the engine 1 is not decelerating, the target opening THCMD is calculated by applying the basic target opening THAP and the idle target opening THIDL to the following equation (1) (step S34). .
THCMD = THAP + THIDL (1)
In step S35, the dashpot control flag FDP is set to "0", and the process ends. The dashpot control flag FDP is referred to in the processing of FIG. 7 described later.
[0029]
If FDEC = 1 in step S33 and the engine 1 is decelerating, it is determined whether or not the cylinder deactivation flag FCYLSTP is "1" (step S36). When FCYLSTP = 0 and the all-cylinder operation is in progress, a THDP calculation process shown in FIG. 7 is executed to calculate a dashpot control term THDP. The dashpot control term THDP is used to gradually reduce the target opening THCMD.
In step S38, the target opening THCMD is calculated by applying the idle target opening THIDL and the dashpot control term THDP to the following equation (2).
THCMD = THIDL + THDP (2)
[0030]
On the other hand, when FCYLSTP is "1" in step S36 and partial cylinder operation is in progress, it is determined whether or not the fuel cut flag FFC is "1". The fuel cut flag FFC is set in the processing of FIG. During the normal operation in which FFC = 0 and the fuel supply to the engine 1 is not interrupted, the target opening THCMD is calculated by the following equation (3) (step S40), and the FFC = 1 and the engine 1 When the fuel cut operation for shutting off the fuel supply to the engine is being performed, the target opening THCMD is calculated by the following equation (4) (step S41).
THCMD = THIDL × KDEC1 (3)
THCMD = THIDL × KDEC2 (4)
[0031]
Here, KDEC1 and KDEC2 are deceleration correction coefficients set to values smaller than “1”, and are set to, for example, “0.5” and “0.8”, respectively. With this setting, when it is determined that the engine 1 is decelerating during the partial cylinder operation, the throttle valve opening TH becomes smaller than during the fuel cut operation before the fuel cut operation is started, and the engine during deceleration is started. The braking effect can be made substantially constant.
[0032]
According to the processing of FIG. 6, the target opening THCMD is set to a smaller value during partial cylinder operation during deceleration of the engine 1 than during full cylinder operation, and the throttle valve is opened. The degree TH is controlled to be small. As a result, during partial cylinder operation, the absolute pressure PBA in the intake pipe becomes substantially the same as during all cylinder operation, and the difference in the effectiveness of engine braking can be eliminated.
[0033]
FIG. 7 is a flowchart of the THDP calculation process executed in step S37 of FIG.
In step S51, it is determined whether or not the dashpot control flag FDP is “0”. Since FDP is initially 0, the process proceeds to step S52, where a THDPB table shown in FIG. 8 is searched according to the engine speed NE to calculate an initial value THDPB of the dashpot control term THDP. The THDPB table is set so that the initial value THDPB increases as the engine speed NE increases.
[0034]
In step S53, the dashpot control term THDP is set to the initial value THDPB, and then the dashpot control flag FDP is set to "1" (step S54). Thereafter, since the answer to step S51 is negative (NO), the process proceeds to step S55.
[0035]
In step S55, the dashpot control term THDP is decremented by a predetermined value α, and then it is determined whether or not the dashpot control term THDP is smaller than “0” (step S56). When THDP ≧ 0, the process is immediately terminated, and when THDP <0, the dashpot control term THDP is set to “0” (step S57).
[0036]
According to the processing in FIG. 7, at the start of deceleration, the dashpot control term THDP is set to the initial value THDPB corresponding to the engine speed NE, and is gradually reduced until it becomes “0”. Therefore, the target opening THCMD is gradually reduced to the idle target opening THIDL (see FIG. 6, step S38). Thus, even when the driver suddenly returns the accelerator pedal, the decreasing speed of the throttle valve opening TH is limited to a speed corresponding to the predetermined value α, so that the throttle valve 3 is not suddenly closed.
[0037]
FIG. 9 is a flowchart of a process for determining an execution condition of the fuel cut operation. This process is executed by the CPU of the ECU 5 in synchronization with the generation of the TDC pulse. In step S61, it is determined whether or not the accelerator pedal operation amount AP is "0". If AP> 0, the down count timer TFCDLY is set to a predetermined time TMFCDLY (for example, 0.3 seconds) and started. (Step S64), and sets the fuel cut flag FFC to "0" (step S65).
[0038]
If the accelerator pedal operation amount AP is “0” in step S61, the NFCT table shown in FIG. 10 is searched according to the engine coolant temperature TW, and the determination rotational speed NFCT is calculated (step S62). In the NFCT table, an upper determination rotation speed NFCTH and a lower determination rotation speed NFCTL are set, and a difference between the two is, for example, 300 rpm. That is, in step S62, the upper determination rotation speed NFCTH and the lower determination rotation speed NFCTL are calculated according to the engine coolant temperature TW. The NFCT table is set such that, before the completion of the warm-up of the engine, the higher the engine coolant temperature TW, the lower the determined rotational speed NFCT.
[0039]
In step S63, it is determined with a hysteresis whether or not the engine speed NE is equal to or lower than the determination speed NFCT. That is, when the fuel cut flag FFC is “0”, the upper determination rotation speed NFCTH is applied, and when the fuel cut flag FFC is “1”, the lower determination rotation speed NFCTL is applied.
[0040]
If NE ≦ NFCT in step S63, the process proceeds to step S64. If NE> NFCT, it is determined whether or not the fuel cut flag FFC has already been set to "1" (step S66). When FFC = 1, this process is immediately terminated. That is, the fuel cut operation is continued.
[0041]
If FFC = 0 in step S66, it is determined whether the value of the timer TFCDLY started in step S64 is "0" (step S67). This process is immediately terminated while TFCDLY> 0, and when TFCDLY = 0, the fuel cut flag FFC is set to "1" (step S68). Thereby, the fuel cut operation is started.
[0042]
In the present embodiment, the cylinder deactivation mechanism 30 constitutes a switching unit, and includes a throttle valve opening sensor 4, an intake air temperature sensor 8, an engine water temperature sensor 9, a crank angle position sensor 10, a vehicle speed sensor 15, a gear position sensor 16, and an accelerator The sensor 17 constitutes operating parameter detection means, the throttle valve 3 corresponds to a control valve, and the actuator 24 and the ECU 5 constitute intake air amount control means. The ECU 5 constitutes a command unit and a deceleration determination unit. More specifically, the processing in FIG. 3 corresponds to the command means, and the processing in FIG. 6 corresponds to the intake air amount control means.
[0043]
The present invention is not limited to the embodiment described above, and various modifications are possible. For example, the target opening THCMD may be calculated by the processing in FIG. This processing is obtained by deleting steps S39 to S41 of the processing shown in FIG. 6 and adding step S42.
[0044]
In step S42, the air conditioner driven by the engine 1 is turned on. That is, when the partial cylinder operation is being performed during the deceleration of the engine 1, the air conditioner is turned on. As a result, the load on the engine 1 increases, and an engine braking effect equivalent to that in the all-cylinder operation can be obtained.
[0045]
Also, if the same engine braking effect as in all-cylinder operation cannot be obtained even when the air conditioner is turned on during partial cylinder operation, steps S39 to S41 in FIG. 6 are used in combination. The throttle valve opening TH may be made smaller than usual. In that case, the deceleration correction coefficients KDEC1 and KDEC2 are set to larger values than the set values when the air conditioner is not turned on.
[0046]
Further, in the above-described embodiment, the throttle valve 3 is used as a control valve, and the intake air amount control means is configured by the actuator 24 and the ECU 5 using a DBW (Drive By Wire) type throttle valve. A linked throttle valve is used, a bypass passage for bypassing the throttle valve, and a bypass air amount control valve for controlling the amount of air sucked through the bypass passage are provided, and the bypass air amount control valve is controlled by the ECU 5. Thus, the intake air amount may be controlled. That is, in this case, the bypass air amount control valve corresponds to the control valve, and the ECU 5 constitutes an intake air amount control unit.
[0047]
The present invention can also be applied to a case where cylinder deactivation is performed in a marine propulsion engine such as an outboard motor having a vertical crankshaft.
[0048]
【The invention's effect】
As described above in detail, according to the first aspect of the invention, when the partial cylinder operation is performed during the deceleration of the engine, the control valve of the intake air amount is more controlled than when the full cylinder operation is performed. Is controlled so as to reduce the opening degree. Therefore, the intake pipe pressure during the partial cylinder operation and the intake pipe pressure during the full cylinder operation become substantially the same, and substantially the same engine braking effect can be obtained.
[Brief description of the drawings]
FIG. 1 is a diagram showing a configuration of an internal combustion engine and a control device thereof according to an embodiment of the present invention.
FIG. 2 is a diagram illustrating a configuration of a hydraulic control system of a cylinder deactivation mechanism.
FIG. 3 is a flowchart of a process for determining a cylinder deactivation condition.
FIG. 4 is a diagram showing a TMTWCSDLY table used in the processing of FIG. 3;
FIG. 5 is a diagram showing a THCS table used in the processing of FIG. 3;
FIG. 6 is a flowchart of a process for calculating a target opening (THCMD) of a throttle valve.
FIG. 7 is a flowchart of a process of calculating a dashpot control term (THDP) executed in the process of FIG. 6;
FIG. 8 is a diagram showing a table used in the processing of FIG. 7;
FIG. 9 is a flowchart of a process for determining an execution condition of a fuel cut operation.
FIG. 10 is a diagram showing a table used in the processing of FIG. 9;
FIG. 11 is a flowchart illustrating a modified example of the process of FIG. 6;
FIG. 12 is a diagram showing a relationship between a throttle valve opening (TH) and an intake pipe absolute pressure (PBA).
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Internal combustion engine 2 Intake pipe 3 Throttle valve (control valve)
4 Throttle valve opening sensor (operation parameter detecting means)
5. Electronic control unit (instruction means, deceleration determination means, intake air amount control means)
8. Intake air temperature sensor (operation parameter detection means)
9 Engine water temperature sensor (operation parameter detection means)
10 Crank angle position sensor (operation parameter detection means)
15 Vehicle speed sensor (driving parameter detection means)
16 gear position sensor (operation parameter detection means)
17 Accelerator sensor (operating parameter detecting means)
24 Actuator (intake air amount control means)
30 cylinder deactivation mechanism (switching means)

Claims (1)

A control device for an internal combustion engine having a plurality of cylinders and having a switching means for switching between an all-cylinder operation for operating all of the plurality of cylinders and a partial-cylinder operation for suspending the operation of some of the plurality of cylinders. ,
Operating parameter detecting means for detecting an operating parameter of a vehicle driven by the engine, including an operating parameter of the engine,
Command means for commanding the switching means to perform the all-cylinder operation or the partial-cylinder operation in accordance with the operation parameter detected by the operation parameter detection means,
A control valve provided in an intake system of the engine to control an intake air amount of the engine;
Intake air amount control means for controlling the opening of the control valve;
Deceleration determining means for determining the deceleration of the engine according to the operating parameter detected by the operating parameter detecting means,
The intake air amount control means, when the deceleration determination means determines that the engine is decelerating, when the partial cylinder operation is being performed, and when the all-cylinder operation is being performed. A control device for an internal combustion engine, wherein the opening degree of the control valve is further reduced.

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